Connector with unitary hinge

ABSTRACT

A connector including a body having an integrally formed unitary hinge portion. The hinge portion connects a cover to a body member for relative movement to a closed position. As the cover is closed, material in the hinge portion deforms in at least two thin narrow strips of material at the bases of parallel grooves. Strain within each thin narrow strip is limited to a predetermined amount by the angle between walls defining the groove.

United States Patent [1 1 Driscoll Feb. 19, 1974 I CONNECTOR WITHUNITARY HINGE [75] Inventor: Aelred D. Driscoll, North St. Paul,

Minn.

[73] Assignee: Minnesota Mining & Manufacturing Company, St. Paul, Minn.

[22] Filed: Mar. 2, 1972 [21] Appl. No.: 231,230

[52] US. Cl 339/98, 16/150, l6/DIG. 13 [51] Int. Cl H01r 13/38 [58]Field of Search 339/59-61, 95,

339/97-99; 16/150, DIG. 13

[56] References Cited UNITED STATES PATENTS Elm 339/98 Enright et al.339/97 R FOREIGN PATENTS OR APPLICATIONS 400,820 4/1966 Switzerland16/150 Primary ExaminerJoseph I-I. McGlynn Attorney, Agent, orFirm-Alexander, Sell, Steldt & DeLaI-Iunt [5 7 ABSTRACT A connectorincluding a body having an integrally formed unitary hinge portion. Thehinge portion connects a cover to a body member for relative movement toa closed position. As the cover is closed, material in the hinge portiondeforms in at least two thin narrow strips of material at the bases ofparallel grooves. Strain within each thin narrow strip is limited to apredetermined amount by the angle between walls defining the groove.

4 Claims, 5 Drawing Figures UNITARY HINGE FIELD OF THE INVENTION Thisinvention relates to electrical connectors of the type having integrallyformed hinge portions.

BACKGROUND OF THE INVENTION Hinge portions integrally formed with thepolymeric body parts of prior art connectors (e.g. US. Pat. Nos.3,388,370 and 3, Ol2, 2 l9 can afford over 180 deg ees of relativemovement between the body parts to attach the connector. Thisdeformation occurs in a single thin strip of material generally definingthe axis of rotation for the hinge portion. In polypropylene hingeportions this thin strip undergoes a strain hardening during its firstdeformation which improves its strength. After strain hardening the thinstrip is highly resistent to fracture even if the connector parts arerelatively moved over 180 degrees when the hinge portion is at a lowtemperature (i.e. below Fahrenheit). However, it has been found that ifthe first deformation of the thin strip occurs when the hinge portion isat a temperature of below 0 Fahrenheit, the incidence of fracture isrelatively high. Such fracture detracts from the reliability of moldedelectrical connectors.

This problem can be averted during production by flexing the thin stripat room temperature before the connector is sold. This procedure,however, adds cost, and may leave the connector parts in unpredictablerelative positions which may affect packaging efficiency and beinconvenient for a craftsman using the connector.

Additionally, certain countries have established flame resistentrequirementsfor electrical connectors. These requirements havenecessitated additives to polypropylene which detract from its favorabledeformation characteristics, or have required the use of new materials.Many of these flame resistent materials do not possess the favorabledeformation characteristics of polypropylene, so that even at roomtemperature they will not deform along a single thin strip of thematerial without fracturing to afford 180 degree relative motion betweenportions parts of the connector.

SUMMARY OF THE INVENTION An integrally formed hinge portion in aconnector according to the present invention distrubutes bending strainwithin the hinge portion between two or more parallel, spaced thinstrips of material, and limits bending within any one thin strip ofmaterial to a predetermined amount. The hinge portion can limit bendingstrain in a thin strip of a given material to an amount which will notproduce fracture under anticipated use conditions so that connectorshaving hinge portions of polypropylene or less deformable materials neednot be flexed during production even if they may be used in below zeroconditions.

BRIEF DESCRIPTION OF THE DRAWING The invention will be more fullyunderstood after reading the following description which refers to theaccompanying drawing in which like numerals designate like partsthroughout the figures, and wherein:

FIG. 1 is an enlarged fragmentary end view showing the unitary hingeportion of a connector according to the present invention with the hingeportion in an open position;

FIG. 2 is an enlarged fragmentary end view showing the unitary hingeportion of FIG. 1 with the hinge portion in a closed position;

FIG. 3 is a top plan view of the connector according to the presentinvention with an open cover attached by the hinge portion of FIG. 1;

FIG. 4 is an end view of the connector of FIG. 3; and

FIG. 5 is an end flew of the connector of FIG. 3 showing the cover inthe closed position.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIGS. 3, 4, and5 there is shown an electrical wire connector 46 according to thepresent invention having a hinge portion 12. The hinge portion 12 isintegrally formed in the body of the connector 46 and connects a firstpart or cover 50 to a second part or body member 52 for 180 degreerelative movement I from an open position (FIGS. 3 and 4) to a closedposition (FIG. 5).

The hinge portion 12, body member 52 and cover 50 are one piece andformed of a deformable polymeric material such as polypropylene. Whenthe body of the connector 46 is formed, (as by molding) a first surfaceon the cover 50 and a second surface 66 on the body member 52 arecoplanar with the cover 50 and the hinge portion 12 in the open positionFIGS. 1, 3 and 4. The hinge portion 12 includes a generally triangularaxially extending hinge segment 28 having its apex 30 approximately inthe plane defined by the surfaces 70 and 66 when they are coplanar. Twopairs of walls 26 define a pair of parallel V-shaped grooves 24 betweenthe body member 52 and the cover 50. The wall 26 are generally of equalheight, and a slight radius may be formed at the abase of each groove24. The thickness of the hinge portion 12 at the base of each groove isnot greater than 0.030 inch (preferably 0.015 inch) along preciselylocated narrow strips 32. The polymeric material in the strips 32 willdeform to afford 180 degree relative movement of the cover 50 and thebody member 52 from the open position to the closed position with thesurfaces 66 and 70 in contact (FIGS. 2 and 5). The pair of walls 26defining each groove 24 are disposed at a predetermined angle to eachother when the surfaces 66 and 70 are coplanar. Relative movement of thecover 50 and the body member 52 toward the closed position will deformthe material in a strip 32 until at least a portion of the walls 26defining the associated groove 24 contact. Thus the angle between thewalls 26 defining each groove 24 will determine the amount of bendingstrain which will occur in the corresponding-strip 32. As the hingeportion 12 is designed to afford 180 degree relative movement betweenthe ea 6r ST and body member SZTt IIe wEIIs 26 defifiiiig" each groove24 are disposed at about a degree angle to equally distribute therequired strain in the hinge portion between the two strips 32 as maybe'desirable to restrict fracture of the strips 32.

The connector 46 affords means for making an electrical connectionbetween the ends of a pair of wires. The connector 46 includes aU-shaped conductive contact element 54 having spaced planar parallellegs 56 with parallel aligned slots formed therein to provide spacedwire engaging fingers 60. The insulative body member 52 is formed with apair of parallel wire receiving cavities 62 extending into the bodymember 52 from inlet openings in the middle of an end wall 57 to anopposite end wall 58. The cavities 62 communicate through openings 64with the top or first surface 66 of the body member 52 to affordinspection of the position of wires in the cavities 62. The body member52 is formed with a pair of slots 68 extending transverse of thecavities 62 from the first surface 66 on the body member 52. The slots68 slidably receive the contact element 54 for movement between a firstposition with the fingers 60 spaced from the cavities 62 to affordpositioning the ends of wires therein (FIG. 4), to a second positionwithin the slots 68 at which the fingers 60 may engage and electricallyconnect the ends of wires in the cavities. in its open position, thecover 50 is positioned with the inner surface 70 coplanar with andspaced from the first surface 66 to afford access to the contact elementto move it to its second position (FlGS. 3 and 4). In the closedposition of the cover 50 (FIG. 5), a flexible hook-like edge wall 72parallel to and opposite the hinge portion 12 is in engagement over alip 74, and the surfaces 66 and 70 are in contact with the cover 50 overthe openings 64 and the end of the engaged contact element 54.

The connector 46 includes latching means to retain the cover 50 in theclosed position. The precisely located lines of bending afforded by thestrips 32 and contact of the walls 26 defining the grooves 24 provideaccurate positioning of the edge wall 72 when the cover 50 has movedsufficiently close to the closed position that an arcuate surface 76along the edge wall 72 will contact an arcuate surface 78 along the lip74. Further pressure on the cover 50 to move it to its closed positionwill cause a camming action between arcuate surfaces 76 and 78 anddeflection in the edge wall 72 and the hinge portion 48 so that the edgewall 72 will move over the lip 74 into latched engagement therewith tomaintain the cover 50 in the closed position.

Hinge portions for connectors may include more than two hinge segments,however the maximum numher is limited as a practical matter by theability to form the thin hinge segments. Within this limitation thenumber of strips 32 between which the strain should be divided in ahinge portion is determined primarily by the characteristics of thematerial in deformation and the angle of relative movement to beprovided by the hinge portion.

Having thus described the present invention, what is claimed is:

1. In a connector for making an electrical connection between wiresincluding a resilient conductive contact element having spaced wirereceiving fingers, and an insulating body member of a polymeric materialhaving wire receiving cavities and a slot extending from a first surfacetransverse to said cavities to slidably receive the contact element formovement from a first position spaced from the cavities to affordpositioning wires therein, to an engaged position with the fingersextending across the cavities to engage wires therein; a cover having asecond surface; a hinge portion integrally formed with and connectingthe body member and the cover for movement of the cover from an openposition with said surfaces spaced to afford manual movement of saidconnector element to the engaged position, to a closed position over thecontact element with said surfaces in contact; and latch means forlatching the cover in the closed position, the improvement wherein: saidhinge portion has converging walls defining at least two spaced parallelgrooves and an intermediate stiff hinge segment having a generallytriangular shape in transverse section and extending parallel to saidgrooves, said segment being connected to the body member and the coverby thin narrow parallel strips of said polymeric material at the basesof the grooves; the strips being deformable by an extent limited bycontact between the walls to afford movement of the cover to the closedposition, and said latch means includes a lip along the edge of saidfirst surface opposite said hinge portion, and a resilient hook-likeedge wall projecting from said second surface along the edge thereofopposite said hinge portion and being adapted for latching engagementover said lip when said cover is in the closed position, said lip andedge wall each having an arcuate surface, and said arcuate surfacesbeing positioned as said cover is moved toward said closed position toengage each other to bias the cover away from said hinge portion to aposition defined by engagement between the walls defining one of thesaid grooves, and to deflect said resilient edge wall to produceengagement thereof over said lip.

2. A connector according to claim 1, wherein said hinge portion has onehinge segment, and said walls are generally planar and define an anglebetween the walls of each groove of about degrees.

3. A connector according to claim 1, wherein said body member and coverare relatively movable through an angle of about degrees between saidopen and closed positions, and the walls are planar and define generallyV-shaped grooves.

4. A connector according to claim 1, wherein said polymeric material ispolypropylene, and said strips have a thickness no greater than about0.03 inch.

UNE'EED STATES PA'lE'N'i ()FFKIE (l-E'Rii Fii'IA'HI OF (IORRECTEONPatent No. 3,193,61Q nawg ppruary 19. 197 6 IflV.nt0f(g) Aelred D.DI'iSCOll It is certified that error appears in the above-identifiedpatent and that said Letters Patent are hereby corrected as shown below:

Column 1, change the title from "UNITARY HINGE" to CONNECTOR WITHUNITARY HINGE and line 49, change "distrubutes" to distributes Column 2,line 29, after "position" insert and after "1" insert line 36, change"wall" to walls and line 37, ohange "abase" to base Signed and sealedthis 1st day of October 1974.

(SEAL) Attest:

McCOY M. GIBSON JR. C. MARSHALL DANN Attesting Officer Commissioner ofPatents USC'OMM-DC 00370-99 n 0.5 GOVIIIIIIIIY "mime om'cl u'u o-au-nl.

FORM PC4080 (10-89)

1. In a connector for making an electrical connection between wiresincluding a resilient conductive contact element having spaced wirereceiving fingers, and an insulating body member of a polymeric materialhaving wire receiving cavities and a slot extending from a first surfacetransverse to said cavities to slidably receive the contact element formovement from a first position spaced from the cavities to affordpositioning wires therein, to an engaged position with the fingersextending across the cavities to engage wires therein; a cover having asecond surface; a hinge portion integrally formed with and connectingthe body member and the cover for movement of the cover from an openposition with said surfaces spaced to afford manual movement of saidconnector element to the engaged position, to a closed position over thecontact element with said surfaces in contact; and latch means forlatching the cover in the closed position, the improvement wherein: saidhinge portion has converging walls defining at least two spaced parallelgrooves and an intermediate stiff hinge segment having a generallytriangular shape in transverse section and extending parallel to saidgrooves, said segment being connected to the body member and the coverby thin narrow parallel strips of said polymeric material at the basesof the grooves; the strips being deformable by an extent limited bycontact between the walls to afford movement of the cover to the closedposition, and said latch means includes a lip along the edge of saidfirst surface opposite said hinge portion, and a resilient hook-likeedge wall projecting from said second surface along the edge thereofopposite said hinge portion and being adapted for latching engagementover said lip when said cover is in the closed position, said lip andedge wall each having an arcuate surface, and said arcuate surfacesbeing positioned as said cover is moved toward said closed position toengage each other to bias the cover away from said hinge portIon to aposition defined by engagement between the walls defining one of thesaid grooves, and to deflect said resilient edge wall to produceengagement thereof over said lip.
 2. A connector according to claim 1,wherein said hinge portion has one hinge segment, and said walls aregenerally planar and define an angle between the walls of each groove ofabout 90 degrees.
 3. A connector according to claim 1, wherein said bodymember and cover are relatively movable through an angle of about 180degrees between said open and closed positions, and the walls are planarand define generally V-shaped grooves.
 4. A connector according to claim1, wherein said polymeric material is polypropylene, and said stripshave a thickness no greater than about 0.03 inch.